Removed the ServiceProcessType enum because a single service process should host all types of services. Also implemeneted a rudimentary singleton mechanism for the service process on Windows.

BUG=None
TEST=Test cloud print proxy and remoting UI.

Review URL: http://codereview.chromium.org/3521012

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@61549 0039d316-1c4b-4281-b951-d872f2087c98

13 files changed, 65 insertions, 82 deletions

diff --git a/chrome/browser/browser_main.cc b/chrome/browser/browser_main.cc
index 1679475..a922f06 100644
--- a/chrome/browser/browser_main.cc
+++ b/chrome/browser/browser_main.cc
@@ -81,7 +81,6 @@
 #include "chrome/common/net/net_resource_provider.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/result_codes.h"
-#include "chrome/common/service_process_type.h"
 #include "chrome/installer/util/google_update_settings.h"
 #include "chrome/installer/util/master_preferences.h"
 #include "grit/app_locale_settings.h"
@@ -1426,7 +1425,7 @@ int BrowserMain(const MainFunctionParams& parameters) {
   if (parsed_command_line.HasSwitch(switches::kEnableRemoting)) {
     if (user_prefs->GetBoolean(prefs::kRemotingHasSetupCompleted)) {
       ServiceProcessControl* control = ServiceProcessControlManager::instance()
-          ->GetProcessControl(profile, kServiceProcessRemoting);
+          ->GetProcessControl(profile);
        control->Launch(NULL);
     }
   }
diff --git a/chrome/browser/printing/cloud_print/cloud_print_setup_flow.cc b/chrome/browser/printing/cloud_print/cloud_print_setup_flow.cc
index 2dfc19f..c6e459a 100644
--- a/chrome/browser/printing/cloud_print/cloud_print_setup_flow.cc
+++ b/chrome/browser/printing/cloud_print/cloud_print_setup_flow.cc
@@ -34,7 +34,6 @@
 #include "chrome/common/net/gaia/google_service_auth_error.h"
 #include "chrome/common/pref_names.h"
 #include "chrome/common/service_messages.h"
-#include "chrome/common/service_process_type.h"
 #include "gfx/font.h"
 #include "grit/locale_settings.h"
 
@@ -93,9 +92,7 @@ class CloudPrintServiceDisableTask
     DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 
     process_control_ =
-        ServiceProcessControlManager::instance()->GetProcessControl(
-            profile_,
-            kServiceProcessCloudPrint);
+        ServiceProcessControlManager::instance()->GetProcessControl(profile_);
 
     if (process_control_) {
       // If the process isn't connected, launch it now.  This will run
@@ -145,9 +142,7 @@ class CloudPrintServiceRefreshTask
     DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 
     process_control_ =
-        ServiceProcessControlManager::instance()->GetProcessControl(
-            profile_,
-            kServiceProcessCloudPrint);
+        ServiceProcessControlManager::instance()->GetProcessControl(profile_);
 
     if (process_control_) {
       // If the process isn't connected, launch it now.  This will run
@@ -351,9 +346,7 @@ void CloudPrintSetupFlow::OnClientLoginSuccess(
   // If we have already connected to the service process then submit the tokens
   // to it to register the host.
   process_control_ =
-      ServiceProcessControlManager::instance()->GetProcessControl(
-          profile_,
-          kServiceProcessCloudPrint);
+      ServiceProcessControlManager::instance()->GetProcessControl(profile_);
 
 #if defined(OS_WIN)
   // TODO(hclam): This call only works on Windows. I need to make it
diff --git a/chrome/browser/remoting/remoting_setup_flow.cc b/chrome/browser/remoting/remoting_setup_flow.cc
index 856fd72..f2c3c33 100644
--- a/chrome/browser/remoting/remoting_setup_flow.cc
+++ b/chrome/browser/remoting/remoting_setup_flow.cc
@@ -27,7 +27,6 @@
 #include "chrome/common/net/gaia/gaia_constants.h"
 #include "chrome/common/net/gaia/google_service_auth_error.h"
 #include "chrome/common/pref_names.h"
-#include "chrome/common/service_process_type.h"
 #include "gfx/font.h"
 #include "grit/locale_settings.h"
 
@@ -41,10 +40,10 @@ static const wchar_t kDoneIframeXPath[] = L"//iframe[@id='done']";
 // is connected or launched. The events are sent back to RemotingSetupFlow
 // when the dialog is still active. RemotingSetupFlow can detach from this
 // helper class when the dialog is closed.
-class RemotingServiceProcessHelper :
-    public base::RefCountedThreadSafe<RemotingServiceProcessHelper> {
+class RemotingServiceProcessHelper
+    : public base::RefCountedThreadSafe<RemotingServiceProcessHelper> {
  public:
-  RemotingServiceProcessHelper(RemotingSetupFlow* flow)
+  explicit RemotingServiceProcessHelper(RemotingSetupFlow* flow)
       : flow_(flow) {
   }
 
@@ -205,9 +204,7 @@ void RemotingSetupFlow::OnIssueAuthTokenSuccess(const std::string& service,
   // If we have already connected to the service process then submit the tokens
   // to it to register the host.
   process_control_ =
-      ServiceProcessControlManager::instance()->GetProcessControl(
-          profile_,
-          kServiceProcessRemoting);
+      ServiceProcessControlManager::instance()->GetProcessControl(profile_);
 
   if (process_control_->is_connected()) {
     // TODO(hclam): Need to figure out what to do when the service process is
diff --git a/chrome/browser/service/service_process_control.cc b/chrome/browser/service/service_process_control.cc
index c3c16d8..6af47c3 100644
--- a/chrome/browser/service/service_process_control.cc
+++ b/chrome/browser/service/service_process_control.cc
@@ -50,7 +50,7 @@ class ServiceProcessControl::Launcher
   }
 
   void DoDetectLaunched(Task* task) {
-    if (CheckServiceProcessRunning(kServiceProcessCloudPrint)) {
+    if (CheckServiceProcessRunning()) {
       ChromeThread::PostTask(ChromeThread::UI, FROM_HERE,
           NewRunnableMethod(this, &Launcher::Notify, task));
       return;
@@ -75,10 +75,8 @@ class ServiceProcessControl::Launcher
 };
 
 // ServiceProcessControl implementation.
-ServiceProcessControl::ServiceProcessControl(Profile* profile,
-                                             ServiceProcessType type)
+ServiceProcessControl::ServiceProcessControl(Profile* profile)
     : profile_(profile),
-      type_(type),
       message_handler_(NULL) {
 }
 
@@ -116,7 +114,7 @@ void ServiceProcessControl::Launch(Task* task) {
   DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 
   // If the service process is already running then connects to it.
-  if (CheckServiceProcessRunning(kServiceProcessCloudPrint)) {
+  if (CheckServiceProcessRunning()) {
     ConnectInternal(task);
     return;
   }
diff --git a/chrome/browser/service/service_process_control.h b/chrome/browser/service/service_process_control.h
index 46c2a18..021b669 100644
--- a/chrome/browser/service/service_process_control.h
+++ b/chrome/browser/service/service_process_control.h
@@ -13,7 +13,6 @@
 #include "base/process.h"
 #include "base/scoped_ptr.h"
 #include "base/task.h"
-#include "chrome/common/service_process_type.h"
 #include "ipc/ipc_sync_channel.h"
 
 class Profile;
@@ -43,16 +42,13 @@ class ServiceProcessControl : public IPC::Channel::Sender,
     virtual void OnGoodDay() = 0;
   };
 
-  // Construct a ServiceProcessControl with |profile| and a specific |type|.
-  ServiceProcessControl(Profile* profile, ServiceProcessType type);
+  // Construct a ServiceProcessControl with |profile|..
+  explicit ServiceProcessControl(Profile* profile);
   virtual ~ServiceProcessControl();
 
   // Return the user profile associated with this service process.
   Profile* profile() const { return profile_; }
 
-  // Return the type of this object.
-  ServiceProcessType type() const { return type_; }
-
   // Return true if this object is connected to the service.
   bool is_connected() const { return channel_.get() != NULL; }
 
@@ -114,7 +110,6 @@ class ServiceProcessControl : public IPC::Channel::Sender,
   void ConnectInternal(Task* task);
 
   Profile* profile_;
-  ServiceProcessType type_;
 
   // IPC channel to the service process.
   scoped_ptr<IPC::SyncChannel> channel_;
diff --git a/chrome/browser/service/service_process_control_browsertest.cc b/chrome/browser/service/service_process_control_browsertest.cc
index 854a7ab..391f99f 100644
--- a/chrome/browser/service/service_process_control_browsertest.cc
+++ b/chrome/browser/service/service_process_control_browsertest.cc
@@ -7,7 +7,6 @@
 #include "chrome/browser/browser.h"
 #include "chrome/browser/service/service_process_control.h"
 #include "chrome/browser/service/service_process_control_manager.h"
-#include "chrome/common/service_process_type.h"
 
 class ServiceProcessControlBrowserTest
     : public InProcessBrowserTest,
@@ -16,7 +15,7 @@ class ServiceProcessControlBrowserTest
   void LaunchServiceProcessControl() {
     ServiceProcessControl* process =
         ServiceProcessControlManager::instance()->GetProcessControl(
-            browser()->profile(), kServiceProcessCloudPrint);
+            browser()->profile());
     process_ = process;
 
     // Launch the process asynchronously.
diff --git a/chrome/browser/service/service_process_control_manager.cc b/chrome/browser/service/service_process_control_manager.cc
index 5750970..5e391a8 100644
--- a/chrome/browser/service/service_process_control_manager.cc
+++ b/chrome/browser/service/service_process_control_manager.cc
@@ -18,7 +18,7 @@ ServiceProcessControlManager::~ServiceProcessControlManager() {
 }
 
 ServiceProcessControl* ServiceProcessControlManager::GetProcessControl(
-    Profile* profile, ServiceProcessType type) {
+    Profile* profile) {
   DCHECK(ChromeThread::CurrentlyOn(ChromeThread::UI));
 
   // TODO(hclam): We will have different service process for different types of
@@ -30,7 +30,7 @@ ServiceProcessControl* ServiceProcessControlManager::GetProcessControl(
   }
 
   // Couldn't find a ServiceProcess so construct a new one.
-  ServiceProcessControl* process  = new ServiceProcessControl(profile, type);
+  ServiceProcessControl* process  = new ServiceProcessControl(profile);
   process_control_list_.push_back(process);
   return process;
 }
diff --git a/chrome/browser/service/service_process_control_manager.h b/chrome/browser/service/service_process_control_manager.h
index c57f65c..a57c43e 100644
--- a/chrome/browser/service/service_process_control_manager.h
+++ b/chrome/browser/service/service_process_control_manager.h
@@ -7,8 +7,6 @@
 
 #include <vector>
 
-#include "chrome/common/service_process_type.h"
-
 class Profile;
 class ServiceProcessControl;
 
@@ -25,12 +23,10 @@ class ServiceProcessControlManager {
   // Get the ServiceProcess instance corresponding to |profile| and |type|.
   // If such an instance doesn't exist a new instance is created.
   //
-  // There will be at most one ServiceProcess for a |profile| and |type|
-  // pair.
+  // There will be at most one ServiceProcess for a |profile|.
   //
   // This method should only be accessed on the UI thread.
-  ServiceProcessControl* GetProcessControl(Profile* profile,
-                                           ServiceProcessType type);
+  ServiceProcessControl* GetProcessControl(Profile* profile);
 
   // Destroy all ServiceProcess objects created.
   void Shutdown();
diff --git a/chrome/common/service_process_type.h b/chrome/common/service_process_type.h
deleted file mode 100644
index 7f80ede..0000000
--- a/chrome/common/service_process_type.h
+++ /dev/null
@@ -1,17 +0,0 @@
-// Copyright (c) 2010 The Chromium Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-#ifndef CHROME_COMMON_SERVICE_PROCESS_TYPE_H_
-#define CHROME_COMMON_SERVICE_PROCESS_TYPE_H_
-
-// Defines different types of service process.
-enum ServiceProcessType {
-  // A service process that hosts a cloud print proxy.
-  kServiceProcessCloudPrint,
-
-  // A service process that hosts a remoting host process.
-  kServiceProcessRemoting,
-};
-
-#endif  // CHROME_COMMON_SERVICE_PROCESS_TYPE_H_
diff --git a/chrome/common/service_process_util.cc b/chrome/common/service_process_util.cc
index df3839c..5cf30df 100644
--- a/chrome/common/service_process_util.cc
+++ b/chrome/common/service_process_util.cc
@@ -32,16 +32,15 @@ std::string GetServiceProcessChannelName() {
 }
 
 // Gets the name of the lock file for service process.
-static FilePath GetServiceProcessLockFilePath(ServiceProcessType type) {
+static FilePath GetServiceProcessLockFilePath() {
   FilePath user_data_dir;
   PathService::Get(chrome::DIR_USER_DATA, &user_data_dir);
   return user_data_dir.Append(FILE_PATH_LITERAL("Service Process Lock"));
 }
 
 #if defined(OS_WIN)
-static std::wstring GetServiceProcessEventName(
-    ServiceProcessType type) {
-  FilePath path = GetServiceProcessLockFilePath(type);
+static std::wstring GetServiceProcessEventName() {
+  FilePath path = GetServiceProcessLockFilePath();
   std::wstring event_name = path.value();
   std::replace(event_name.begin(), event_name.end(), '\\', '!');
   return event_name;
@@ -49,18 +48,33 @@ static std::wstring GetServiceProcessEventName(
 
 // An event that is signaled when a service process is running. This
 // variable is used only in the service process.
-static ScopedHandle service_process_running_event;
+static HANDLE g_service_process_running_event;
 #endif
 
-void SignalServiceProcessRunning(ServiceProcessType type) {
+bool TakeServiceProcessSingletonLock() {
 #if defined(OS_WIN)
-  std::wstring event_name = GetServiceProcessEventName(type);
+  std::wstring event_name = GetServiceProcessEventName();
+  DCHECK(g_service_process_running_event == NULL);
+  ScopedHandle service_process_running_event;
   service_process_running_event.Set(
-      CreateEvent(NULL, true, true, event_name.c_str()));
+      CreateEvent(NULL, TRUE, FALSE, event_name.c_str()));
+  DWORD error = GetLastError();
+  if ((error == ERROR_ALREADY_EXISTS) || (error == ERROR_ACCESS_DENIED))
+    return false;
   DCHECK(service_process_running_event.IsValid());
+  g_service_process_running_event = service_process_running_event.Take();
+#endif
+  // TODO(sanjeevr): Implement singleton mechanism for other platforms.
+  return true;
+}
+
+void SignalServiceProcessRunning() {
+#if defined(OS_WIN)
+  DCHECK(g_service_process_running_event != NULL);
+  SetEvent(g_service_process_running_event);
 #else
   // TODO(hclam): Implement better mechanism for these platform.
-  const FilePath path = GetServiceProcessLockFilePath(type);
+  const FilePath path = GetServiceProcessLockFilePath();
   FILE* file = file_util::OpenFile(path, "wb+");
   if (!file)
     return;
@@ -69,20 +83,21 @@ void SignalServiceProcessRunning(ServiceProcessType type) {
 #endif
 }
 
-void SignalServiceProcessStopped(ServiceProcessType type) {
+void SignalServiceProcessStopped() {
 #if defined(OS_WIN)
   // Close the handle to the event.
-  service_process_running_event.Close();
+  CloseHandle(g_service_process_running_event);
+  g_service_process_running_event = NULL;
 #else
   // TODO(hclam): Implement better mechanism for these platform.
-  const FilePath path = GetServiceProcessLockFilePath(type);
+  const FilePath path = GetServiceProcessLockFilePath();
   file_util::Delete(path, false);
 #endif
 }
 
-bool CheckServiceProcessRunning(ServiceProcessType type) {
+bool CheckServiceProcessRunning() {
 #if defined(OS_WIN)
-  std::wstring event_name = GetServiceProcessEventName(type);
+  std::wstring event_name = GetServiceProcessEventName();
   ScopedHandle event(
       OpenEvent(SYNCHRONIZE | READ_CONTROL, false, event_name.c_str()));
   if (!event.IsValid())
@@ -91,7 +106,7 @@ bool CheckServiceProcessRunning(ServiceProcessType type) {
   return WaitForSingleObject(event, 0) == WAIT_OBJECT_0;
 #else
   // TODO(hclam): Implement better mechanism for these platform.
-  const FilePath path = GetServiceProcessLockFilePath(type);
+  const FilePath path = GetServiceProcessLockFilePath();
   return file_util::PathExists(path);
 #endif
 }
diff --git a/chrome/common/service_process_util.h b/chrome/common/service_process_util.h
index 37ea33c..5f54f75 100644
--- a/chrome/common/service_process_util.h
+++ b/chrome/common/service_process_util.h
@@ -7,8 +7,6 @@
 
 #include <string>
 
-#include "chrome/common/service_process_type.h"
-
 class Profile;
 
 // Return the IPC channel to connect to the service process.
@@ -19,14 +17,20 @@ std::string GetServiceProcessChannelName();
 // The following methods are used as a mechanism to signal a service process
 // is running properly and all initialized.
 //
+
+// Tries to become the sole service process for the current user data dir.
+// Returns false is another service process is already running.
+bool TakeServiceProcessSingletonLock();
+
 // Signal that the service process is running.
 // This method is called when the service process is running and initialized.
-void SignalServiceProcessRunning(ServiceProcessType type);
+void SignalServiceProcessRunning();
 
 // Signal that the service process is stopped.
-void SignalServiceProcessStopped(ServiceProcessType type);
+void SignalServiceProcessStopped();
 
-// This method checks that if the service process is running.
-bool CheckServiceProcessRunning(ServiceProcessType type);
+// This method checks that if the service process is running (ready to receive
+// IPC commands).
+bool CheckServiceProcessRunning();
 
 #endif  // CHROME_COMMON_SERVICE_PROCESS_UTIL_H_
diff --git a/chrome/service/service_main.cc b/chrome/service/service_main.cc
index f71c405..b0765fa 100644
--- a/chrome/service/service_main.cc
+++ b/chrome/service/service_main.cc
@@ -9,11 +9,16 @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/main_function_params.h"
 #include "chrome/common/sandbox_policy.h"
+#include "chrome/common/service_process_util.h"
 #include "chrome/service/cloud_print/cloud_print_proxy.h"
 #include "chrome/service/service_process.h"
 
 // Mainline routine for running as the service process.
 int ServiceProcessMain(const MainFunctionParams& parameters) {
+  // If there is already a service process running, quit now.
+  if (!TakeServiceProcessSingletonLock())
+    return 0;
+
   MessageLoopForUI main_message_loop;
   if (parameters.command_line_.HasSwitch(switches::kWaitForDebugger)) {
     DebugUtil::WaitForDebugger(60, true);
diff --git a/chrome/service/service_process.cc b/chrome/service/service_process.cc
index 821bfd2..86d787b 100644
--- a/chrome/service/service_process.cc
+++ b/chrome/service/service_process.cc
@@ -19,7 +19,6 @@
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/json_pref_store.h"
 #include "chrome/common/pref_names.h"
-#include "chrome/common/service_process_type.h"
 #include "chrome/common/service_process_util.h"
 #include "chrome/service/cloud_print/cloud_print_proxy.h"
 #include "chrome/service/service_ipc_server.h"
@@ -113,7 +112,7 @@ bool ServiceProcess::Initialize(MessageLoop* message_loop,
 
   // After the IPC server has started we signal that the service process is
   // running.
-  SignalServiceProcessRunning(kServiceProcessCloudPrint);
+  SignalServiceProcessRunning();
 
   // See if we need to stay running.
   ScheduleShutdownCheck();
@@ -142,7 +141,7 @@ bool ServiceProcess::Teardown() {
   network_change_notifier_.reset();
 
   // Delete the service process lock file when it shuts down.
-  SignalServiceProcessStopped(kServiceProcessCloudPrint);
+  SignalServiceProcessStopped();
   return true;
 }